Dec. 5 (UPI) -- China may have recently conducted air force drills to send a message to the United States and South Korea, while flying near the peninsula to collect military intelligence.
Chinese air force spokesman Shen Jinke said Monday the exercises involved aircraft traveling along "routes and areas it has never flown before," the South China Morning Post reported Tuesday.
The Chinese spokesman did not provide details on dates, but the announcement came the same day Washington and Seoul launched their biggest joint air force exercise.
Reconnaissance planes, fighter jets, an early warning and control aircraft, were included in the exercise, according to Beijing.
Li Jie, a Chinese military expert based in Beijing, said the announcement was targeting the United States and South Korea.
"The timing of this high-profile announcement by the PLA is also a warning to Washington and Seoul not to provoke Pyongyang any further," he said.
Song Zhongping, an independent commentator for Hong Kong-based Phoenix Satellite Television, said China may have flown over China's air defense identification zone, or ADIZ, in the East China Sea.
Those areas overlap with Japanese and South Korean airspace.
Surveillance equipment may have also been used to collect data on military deployments on the Korean peninsula, Song added.
The United States and South Korea deployed THAAD, a U.S. missile defense system, that is strongly opposed in Beijing.
China claims missile defense can be used to track movements within its borders.
U.S. Forces in Japan may be preparing future provocations with navy patrols.
South Korean newspaper Seoul Shinmun reported Tuesday from Yokosuka naval base the nuclear-powered aircraft carrier Ronald Reagan was north of the Philippines, on a patrol mission.
The U.S. crew at the base are ready at all times to respond to crisis on the peninsula, according to the report.